Scientists like Ignacio Taboada, an assistant professor in the Georgia Tech School of Physics, are using a one cubic kilometer block of ice at the South Pole to help unravel one of the great scientific mysteries of our time.
A 250 TeV neutrino interaction in IceCube.
At the neutrino interaction point (bottom), a large particle shower is visible, with a muon produced in the interaction leaving up and to the left.
The direction of the muon indicates the direction of the original neutrino.
Image Credit: NSF
The IceCube Neutrino Observatory at the South Pole is a telescope like no other on Earth.
This giant structure buried deep beneath the Antarctic ice has done what no other telescope or space probe could, it has discovered the first neutrinos from outside our solar system.
IceCube’s discovery has created a whole new frontier for astronomers. One where scientists don’t just observe giant objects from distant galaxies, but the tiny particles that form them.
This discovery may help scientists explain supernovae, black holes, pulsars, active galactic nuclei and other extreme extra-galactic phenomena.
The IceCube Observatory at the Amundsen-Scott South Pole Station, in Antarctica.
Image Credit: Sven Lidstrom, Intensive research
Neutrinos are tiny, near-massless particles created by “cosmic accelerators”.
These are violent astrophysical sources such as exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars.
Neutrinos aren’t rare: our sun creates 65 billion neutrinos every second for every square centimetre of Earth, but neutrinos from outside the solar system are extremely hard to detect; partly because they are so incredibly small, but also because we are swamped with billions upon billions from inside our own solar system.
The IceCube Observatory has found 28 needles in this metaphorical haystack, 28 neutrinos that scientists are convinced are from outside our solar system.
The hot water drill manages to bore deep holes through the Antarctic ice.
Image Credit: NSF
Currently the IceCube can’t tell us the exact origins of the neutrinos but they have speculated on the direction and general area.
According to Science magazine: “the origin of this flux is unknown, the findings are consistent with expectations for a neutrino population with origins outside the solar system.”
The IceCube Observatory was designed for this very purpose. It is a unique structure consisting of 86 strings drilled deep into the Antarctic ice.
Attached to these strings are 5,160 digital optical modules, which are embedded between 1.4 and 2.4km below the Antarctic ice.
"IceCube is a wonderful and unique astrophysical telescope.” said Vladimir Papitashvili, Antarctic astrophysics and geospace science programme director with the National Science Foundation.
“It is deployed deep in the Antarctic ice, but looks over the entire universe."
The IceCube Observatory consists of 86 arrays dug almost two and a half kilometres into the ice.
Image credit: Nasa-verve, Wikipedia
How it works
Neutrinos carry information about the workings of the most distant phenomena in the universe.
But it’s hard to capture /measure neutrinos because they are near massless, and carry no electrical charge.
Neutrinos are not affected by electromagnetic forces, and pass straight through matter, including the Earth.
They do, however, causes tiny flashes of blue light, called Cherenkov light, when they interact with the ice. It is these tiny blue flashes deep beneath the South Pole that IceCube has been built to monitor.
A Digital Optical Module (DOM) being attached to the final string just before the detector array was switched online
Image Credit: Peter Rejcek, NSF
Rather than looking into the sky, the IceCube monitor has over five thousand Digital Optical Modules (DOMs).
Each one has a photomultiplier tube (PMT) and a data acquisition computer. A PMT is a vacuum tube that is extremely sensitive to light in the ultraviolet, visible and near-infrared range.
It can multiply the current produced by such light by as much as 100 million times.
Digital Optical Modules are suspended on strings in holes melted into the ice using a hot water drill, at depths ranging from 1,450 to 2,450 metres
Image Credit: Amble, Wikipedia
Breaking the ice
These DOMs are attached to 86 different strings that have been buried deep beneath the ice.
Scientists used a hot water drill to bore holes with depths ranging from 1,450 to 2,450 metres and suspended the DOMs on the strings beneath the ice.
The photomultiplier tube inside the DOM scans for the Cherenkov effect, and the on-board computer sends any data back to the surface.
According to the National Science Foundation the observation of 28 very high-energy particle events constitutes the first solid evidence for astrophysical neutrinos from cosmic accelerators.
"This is the first indication of high-energy neutrinos coming from outside our solar system," says Francis Halzen, principal investigator of IceCube and the Hilldale and Gregory Breit Distinguished Professor of Physics at the University of Wisconsin-Madison.
"It is gratifying to finally see what we have been looking for. This is the dawn of a new age of astronomy."
At the neutrino interaction point (bottom), a large particle shower is visible, with a muon produced in the interaction leaving up and to the left.
The direction of the muon indicates the direction of the original neutrino.
Image Credit: NSF
The IceCube Neutrino Observatory at the South Pole is a telescope like no other on Earth.
This giant structure buried deep beneath the Antarctic ice has done what no other telescope or space probe could, it has discovered the first neutrinos from outside our solar system.
IceCube’s discovery has created a whole new frontier for astronomers. One where scientists don’t just observe giant objects from distant galaxies, but the tiny particles that form them.
This discovery may help scientists explain supernovae, black holes, pulsars, active galactic nuclei and other extreme extra-galactic phenomena.
Image Credit: Sven Lidstrom, Intensive research
Neutrinos are tiny, near-massless particles created by “cosmic accelerators”.
These are violent astrophysical sources such as exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars.
Neutrinos aren’t rare: our sun creates 65 billion neutrinos every second for every square centimetre of Earth, but neutrinos from outside the solar system are extremely hard to detect; partly because they are so incredibly small, but also because we are swamped with billions upon billions from inside our own solar system.
The IceCube Observatory has found 28 needles in this metaphorical haystack, 28 neutrinos that scientists are convinced are from outside our solar system.
Image Credit: NSF
Currently the IceCube can’t tell us the exact origins of the neutrinos but they have speculated on the direction and general area.
According to Science magazine: “the origin of this flux is unknown, the findings are consistent with expectations for a neutrino population with origins outside the solar system.”
The IceCube Observatory was designed for this very purpose. It is a unique structure consisting of 86 strings drilled deep into the Antarctic ice.
Attached to these strings are 5,160 digital optical modules, which are embedded between 1.4 and 2.4km below the Antarctic ice.
 |
| Vladimir Papitashvili |
“It is deployed deep in the Antarctic ice, but looks over the entire universe."
Image credit: Nasa-verve, Wikipedia
How it works
Neutrinos carry information about the workings of the most distant phenomena in the universe.
But it’s hard to capture /measure neutrinos because they are near massless, and carry no electrical charge.
Neutrinos are not affected by electromagnetic forces, and pass straight through matter, including the Earth.
They do, however, causes tiny flashes of blue light, called Cherenkov light, when they interact with the ice. It is these tiny blue flashes deep beneath the South Pole that IceCube has been built to monitor.
Image Credit: Peter Rejcek, NSF
Rather than looking into the sky, the IceCube monitor has over five thousand Digital Optical Modules (DOMs).
Each one has a photomultiplier tube (PMT) and a data acquisition computer. A PMT is a vacuum tube that is extremely sensitive to light in the ultraviolet, visible and near-infrared range.
It can multiply the current produced by such light by as much as 100 million times.
Image Credit: Amble, Wikipedia
Breaking the ice
These DOMs are attached to 86 different strings that have been buried deep beneath the ice.
Scientists used a hot water drill to bore holes with depths ranging from 1,450 to 2,450 metres and suspended the DOMs on the strings beneath the ice.
The photomultiplier tube inside the DOM scans for the Cherenkov effect, and the on-board computer sends any data back to the surface.
According to the National Science Foundation the observation of 28 very high-energy particle events constitutes the first solid evidence for astrophysical neutrinos from cosmic accelerators.
 |
| Francis Halzen |
"It is gratifying to finally see what we have been looking for. This is the dawn of a new age of astronomy."
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